The invention relates to medicine, and more particularly it relates to methods of cytological diagnosis for cancer and precancer conditions, and can therefore be used in medical practice, scientific research, and prophylaxis.
The proposed method can also be used for prophylactic examination of populations on a mass scale for early revealing oncological diseases.
The invention can be used for diagnosis of cells by their size taken from cytological material of the patient, such as biopsy material, washing waters, vaginal scrapes, exudate, and pathological secretion, which cells are fixed and stained by methods suitable for measuring areas of the nucleus and the cell. The cell area can be determined in micrometers, planimeters, etc., and also by various other modes.
Various measuring and computing apparati for the automation of cytological diagnosis of cancer and pre cancer conditions has evoked interest as to dimensional signs as the most promising criterion in the technical realization of diagnosing cytological preparations. On the one hand, it is common knowledge that malignant processes are characterized by the increased area of the cell nucleus. As far back as in 1952, Johnston proposed that the ratio of the cell nucleus to the cytoplasm should be used as a criterion for diagnosing cancer and precancer conditions. On the other hand, technical means have been developed that can be used to measure the linear dimensions of micro-object images, for example, by analyzing usually the image from a scanning electron microscope.
However, the practical measurement of areas of nuclei and cytoplasm in more than two thousand cells in normal, precancer, and cancer cytological preparations, and the subsequent analysis, have shown that the size of the area of the cell nucleus is a less important criterion for diagnosing cancer and precancer conditions compared with the ratio of the area of the nucleus to the area of the cytoplasm in the cell.
Methods for cytological diagnosis of cancer conditions are known in the prior art, which consist of measuring the following: the ratio of the nucleus area to the area of the cell; the optical density of the nucleus; and the DNA and RNA content of the cell. The known methods, however, have certain disadvantages, which are as follows: it is impossible to differentiate precancer and cancer conditions using only one sign as a criterion; the difficulties encountered by the Examiner in measuring the areas of the cells and their nuclei are not justified by the low trustworthiness of the diagnosis;
It is necessary to measure a great number of cells in the preparation, while some cytological preparations only contain insignificant quantities of pathologically modified cells (atypical cells) and cannot therefore be used for diagnostic purposes; and at the same time, the assessment of the other preparations require much additional time.